The present invention relates to an improved golf club head, and more particularly, the invention relates to the improvement in shooting of golf balls by a golf club head containing a fiber reinforced plastic (FRP) element.
Although the following descriptions are directed to iron golf club heads, the present invention is also applicable to wooden golf club heads, as evidenced by the later disclosed example.
One typical example of the conventional iron golf club head has a main body made of stainless steel, cast iron or brass. Another conventional iron golf club head has a main body which is made up of a metallic core, a metallic sole section and an FRP shell covering the core and the face side section. In particular, an iron golf club head with a CFRP (carbon fiber reinforced plastics) shell has greatly gained the attention of golf players.
Since the face side surface is provided by a highly elastic CFRP shell, the iron golf club head of this type assures significantly long distance shooting of balls, reduced weight of the head and correct shooting in the intended direction.
When wholly made of metal, such a golf club head cannot assure ideal feel during shooting. In addition, no local weight adjustment can be effected inasmuch as the main body is made of a single material of uniform specific gravity. This disenables free inertia moment adjustment of the golf club head.
When an FRP shell is employed, the face side surface provided by a CFRP shell is rather vulnerable to damage. Combination of a heavy core with a light shell again does not allow easy and free inertia moment adjustment. Further, since the metallic core is arranged behind the CFRP providing the face side surface, the characteristics of the CFRP is subdued by influence of characteristics of the metallic material.